As the power levels of microprocessors and other electronic components continue to increase to provide higher levels of performance, the task of cooling these microprocessors as they operate becomes more of a challenge. As illustrated in FIG. 1, one conventional approach to cooling microprocessors includes mounting a heat sink to the microprocessor and forcing air over the heat sink to effectuate cooling thereof. The conventional heat sink 10 typically includes a base 12 mounted to the microprocessor 14 and a plurality of generally planar fins 16 projecting from base 12 in a substantially perpendicular manner. More particularly, the fins 16 are generally configured as rectangular bars or plates in spaced apart relation across a length of base 12 to define flow channels 18 therebetween. Air from a fan (not shown), for example, is directed into the flow channels 18 so as to flow across the major surfaces of the fins 16 and provide cooling to microprocessor 14.
While such conventional heat sinks as described above are common, there are some drawbacks to their use in some applications for which cooling of microprocessors is desired. For example, one such drawback is that conventional heat sinks are relatively large in size in order to provide adequate cooling of the microprocessor. In some applications, however, the amount of space within a cabinet, housing, or other enclosure about the microprocessor is very limited and providing adequate cooling becomes a major design challenge. It is believed that the relatively large size of conventional heat sinks 10 may be due to an inefficient use of the available surface area and the fluid flowing through the flow channels 18. In this regard, and as illustrated in FIG. 1, the flow channels 18 are typically open along an upper end 20 thereof. Thus, as air is directed into the flow channels 18, as illustrated by arrows A, the air is heated and starts to rise and flow out of the upper end 20 of the heat sink 10, as illustrated by arrows B. Accordingly, a relatively low volume of air flows across the full extent (e.g., width) of the fins 16 so as to exit the end opposite the air inlet. Therefore, the surface area of the fins 16 adjacent the exit end of the flow channels 18 is not efficiently utilized to effectuate heat transfer from the microprocessor 14. In addition, the planar sides of the fins 16 facilitate generally smooth, laminar type flow through the channels 18, which may reduce the amount of heat transfer compared to a more chaotic, turbulent flow pattern.
Accordingly, there is a need for an improved heat sink that makes more efficient use of the available surface area and air flowing therethrough so as to permit a relatively smaller, low profile design capable of providing adequate cooling to the microprocessor.